IDEA-146649 "Redundant type cast" warning expected when casting primitive to the same type

GitOrigin-RevId: 1ee7941e5f78e525a3edd92f539e21bd720b096e

java/java-psi-api/src/com/intellij/psi/util/RedundantCastUtil.java

@@ -469,17 +469,22 @@ public class RedundantCastUtil {
 
       final PsiType topCastType = typeCast.getType();
       if (expr instanceof PsiTypeCastExpression) {
-        PsiTypeElement typeElement = ((PsiTypeCastExpression)expr).getCastType();
+        PsiTypeCastExpression innerCast = (PsiTypeCastExpression)expr;
+        PsiTypeElement typeElement = innerCast.getCastType();
         if (typeElement == null) return;
         PsiType castType = typeElement.getType();
-        final PsiExpression innerOperand = ((PsiTypeCastExpression)expr).getOperand();
+        final PsiExpression innerOperand = innerCast.getOperand();
         final PsiType operandType = innerOperand != null ? innerOperand.getType() : null;
         if (!(castType instanceof PsiPrimitiveType) && !(topCastType instanceof PsiPrimitiveType)) {
           if (operandType != null && topCastType != null && TypeConversionUtil.areTypesConvertible(operandType, topCastType)) {
-            addToResults((PsiTypeCastExpression)expr);
+            addToResults(innerCast);
           }
         } else if (Comparing.equal(PsiPrimitiveType.getUnboxedType(operandType), topCastType)) {
-          addToResults((PsiTypeCastExpression)expr);
+          addToResults(innerCast);
+        }
+        else if (operandType != null && operandType.equals(castType)) {
+          // like (int)(long)1L
+          addToResults(innerCast);
         }
       }
       else {

java/java-tests/testData/inspection/redundantCast/generics/CastLongLiteral.java

@@ -0,0 +1,7 @@
+import org.jetbrains.annotations.*;
+
+class A {
+  void method() {
+    int v = (int)(<warning descr="Casting '1L' to 'long' is redundant">long</warning>)1L;
+  }
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/RedundantCast15Test.java

@@ -80,4 +80,5 @@ public class RedundantCast15Test extends LightCodeInsightFixtureTestCase {
   public void testDifferentNullness() { doTest();}
 
   public void testPrimitiveWidening() { doTest(); }
+  public void testCastLongLiteral() { doTest(); }
 }